Bedheels markets many of their heels as "Just for bedroom, not for walking" so the shank might be bendy because the shoe is for - well, crawling around...
I have similar ones (smaller size though) and me most likely being, as a female, lighter than aplhax, the shanks do bend a bit under my weight and have to say, to make the walk feel more secure and sturdier you'd expect the shoe to widhstand the pressure without feeling like it's going to buckle. But, those heels are extremely high and to produce a shank that doesn't bend, you would probably have to pay much more than you pay for Bedheels, which otherwise seem to be of fairly good quality for the price range.

Ruling out the ancient suicide shifters with hand-operated gear shift - but then in turn you had a foot-operated clutch.
As for riding with heels, technically doable but I would advice against it. Small shoe size alone makes it a reach when shifting, wearing stilts doesn't really help. You can slip the foot peg between the sole and the heel making it possible to reach further but you risk damaging the heels and when leaning on to the turn, even scraping the ground. And speaking of experience, been there done that.

Pianist/keboard player/organist... Remember thousand years ago thought it would be ROCK to wear some crazy high heels on a gig with my organ with bass pedals... Except during the first three bars of the first song, got my heel stuck between the pedals about gazillion times.
I still appear on stage on high heels but once behind the B3 I slip them off, lesson learned.

Depending on the day and mood, anything from flats to 7" heel with a platform...
If I know I'm going to be alone for the day - small office, ha - in addition to some too-high-to-walk heels I sometimes wear full latex and then pretend I get work done instead of... you get the picture.

I'm a smurf so the extra height is welcome, also on my shoe size (36) the toe box might look ridiculously small, deppending on the shoe type so a small platform might make the shoe look more in proportions.

How tall are you?
159,5 cm/ just under 5ft 3in. Smurfette.
Are you happy with your height?
Totally. Ima pocket rocket!
To be honest, sometimes it pisses me off at the stores, to reach the not even top shelves, and there's other similar things but... there's always the high heels.
Does your height have any bearing on why you wear heels?
At least as an excuse, maybe - I need the stilts to get to the same level with the rest of the world, hehe.
What would be your perfect height?
I'm perfect in evey way already.
How does your height compare to your partner?
She's about 2½ in taller so close enough!

For my shoe size of 36, a 14 cm/5.5"heel without a platform is sort of a maximum to be able to properly walk with and I can survive those through the day. I do have a couple of higher ones, though, that force the feet completely vertical, making it almost impossible to stand in them but those are perfect for fetish games. Like Charlotte put it, there's no such thing as too high, sometimes you just need to crawl..

Drawn between cobbled streets and broken pavements - plenty of cobble stones at downtown area, on the other hand the frost sometimes cracks the streets. But it also depends on the shoes and heel type, and also on what else you are wearing; if I venture outside in miy ultra-high shoes, everything is a problem, in addition if I dare to wear a hobbling skirt, I become a helpless klutz who can'tcross the street without stumbling (but that would be the idea in the first place, no?)